Thitr



(No Model.)

F. A. MGARTHUR.

ENGINBBRS BRAKE VALVE.V

Patented Sept. 30, 1884.

wf@ j N. PETERa Hwwmmgnpnnr. wanhingmn, n, C.

l TEUR, of Detroit, in the county of Wayne and State of Michigan, have invented new and use called the engineers brake-valve, and it between thereservoir kand the brake-pipe when `ilow of air from the main reservoir into the `most positive operation oi' the brakes.

UNITED rires.

FREDERICK A. Menem-Inn, or DETROIT, MICHIGAN, Assienon or one' HALF jro n. n. E. oowELL ANDQE. n. snowman, or SAME PLAGE. I

SPECIIIICATEON forming part of Letters Patent No.

305,831, dated September 30, 1884.,

Application filed May 15, 1884. (No model.)

To @il whom may concern.

Be it known that I, FREDERICK A. Moen-V ful Improvements in Engineers7 Brak e-Valves and I hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, which forni a part of this speciiication.

This invention relates to an improvement in three-way valves for air-brakes. In automatic air-brakes-suoh as the Testinghouse automatic brake-the engineer exercises control overihe air-brakes by means of a three-way cock valve placed in the cab, and commonly is this valve my improvement refers to. VBy means of this valve the engineer regulates the brakepipe for releasing the brakes, and from the brake-pipe tothe atmosphere for applying the brakes. In the improved Westinghouse air-brake a new style of an engineers brake-valve has been introduced, by means of which, when the communication between the brake-pipe and t-he reservoir is cut oif by av certain position of the valve called the running position, a secondary communication between the reservoir and the brake-pipe is established, allowing enough air to pass from the reservoir into the brake-pipe to provide against leakage in the latter, while it main tains at thesame time a diii'erential pressure between the reservoir and the trainpipe-that is to say, it maintains in the brake-pipe an air-pressure of about sixty pounds, while the pressure V.in the reservoir is twenty pounds higher. The threeway coclr,'which is still in extended use on the V-estinghouse Vair-brake as an engineers brake-valve, cannot produce in its present construction this new condition, which is found very desirable to insure the It is the object of Inyinvention to adapt the three-way valve as it is now in use as an engineers brake-valve Ato produce this new resultthat is, to maintain a differential pressure the valve is put in a certain position called the running position5 and my invention consists in the new arrangement and construc- Vthe port tion of certain parts bymeans of which I have obtained Jthis object, all as hereinafter described.

In the drawings which accompany this specification, Figurel is a plan of my improved brakevalve. Figs. 2, 3, 4, and 5 are like hori-r zontal sections illustrating `four different po1 sitions of the valve-plug, and which are especially referred to hereinafter. Fig. 6 is a perspective of my tive of the valve-plug, partly in section, to

i show the construction of the differential valve placed in its body. Fig. 8 is a detachedpervation of my valve, showing it connected.

A is the shell of the valve, provided with the ports B C I), the iirst lconnecting thevalve with the main reservoir It through a pipe, E.

The second port connects with the brake-'pipe Y F, and the third with the exhaust-pipe G.

H isthe valvecoclr, provided with the ports I and K and the handle L, for operating it.

M is a bent leafspring, secured upon the handle, and exerting its tension against the periphery of the collar or ring N, which embraces t-he upper end of the valve-cock, and is held in position by the nut c, which also secures the valve in position upon a plateV or bracket b, as shown in Fig. l;

6o valve with the shell partly broken away. Fig. 7 is a detached perspec` spective of the index-collar. Fig. 9 is an ele- The parts so far described constitute' the engineers brake-valve as it has been in use heretofore, and Fig. 2 shows the position of the cock for establishing the communication 'between the main reservoir and the brake-v pipe, Vwhile Fig. 5 shows its position for exhausting the air from the brake-pipe. This t construction I have improved inthe following manner: I form in the `upper part oi' the valvecock and centrally thereto a valve-chamber, O, provided with the valve-seat c. In this chamber I place apuppet-valve, I), around the stem of which is placed the coil-spring Q.,

the tension of which presses the valve upon its seat. Through the body oi the cock I drill two small ports, dl c, the former leading into the valve-chamber below the valve and the latter in the valve-chamber above the valve.

In the valveseat of the shell A ofthe valve I form two small vertical channels, g il, (sec Fig. 6,) one directly above-the upper end of B andthe otheruabove the port C. The channels g hand ports cl e are in such rel the puppet-valve.

ative positions that when the cock of the valve is placed in the position shown in Figs. 3 and 6 the port d registers with the channel g and the port e with the channel h. Now, as the channel g connects with the port B and the channel h with the port O, it is clear that in this position of the cock communication will be established between the main reservoir and the brake-pipe by means of the ports d e whenever the resistance or load of the puppet-valve P is overcome by the difference in the airpressures between the main reservoir and the brake pipe. In practice a load of about .twenty pounds to the ,square inch is put on The parts d e need only to be of sufficient area to allow enough air to pass from the reservoir into the brake-pipe to make up for leakage in the latter, so as to easily maintain the required airpressure in the brake-pipe while the train is running, and which pressure is in practice fixed at about sixty pounds, while the pressure in the reservoir is about eighty pounds` To mark to the engineer the proper position in which to place his handle to obtain the function of the ports d e, as above described, I place a stop, i, in the ring N, so that the engineer can easily feel, by the increased resistance of his handle against the shoulder, whenhe is in this position, which is now the one he hasL to keep while running, instead of the position shown in Fig. 2, which he keeps with the old valve. The increased number of ports now makes it also desirable to mark to the engineer the exact position in which all his ports lap, which is the position shown in Fig. 4, and wherein all communication between the main reservoir and the off. As this position is close to the running position in Fig. 3,-I make the stop z' of proper peripheral length to form the shoulders j andl lc in exact position to form stops, the former for the ruiming position and the latter for the lap position77 of the handle.

To provide against the wear of the parts, I make the channels g h about a quarter of an inch long7 and place the ports d ehigh enough to register with the upper ends of these channels, so that as the valve-faces wear off the ports d e will yet register with the channels.

One advantage of my improved brake-valve is that my improvement can be easily and cheaply applied to the old style brake-valve,

which would be otherwise superseded by an4 entirely new and different valve, which, aside from the larger expense, presents the great drawback of being unfamiliar to the engineer, so that there is great danger that in' sudden emergencies he may get confused, or at least not be able to act with the necessary promptness.

rlhe operation of my improved brake-valve does not introduce a single new element liable to confuse an engineer to whom the old brake-valve has become familiar. It simply denes two positions of. the brake-handlethe running position and the lap positionbrake-pipe is cut' .which formerly were obtained with a slightly different position of the handle.

Another advantage of my improvement is that it does not impair the simplicity and efthe minor ports d e, which form an air-pas sagethrough the cock, controlled by a differential pressure-valve placed within the body of the cocksuch as the spring puppet-valve O-in combination withA ports in the shell of the valve, adapted to register therewith, and connecting with two of the main ports of the valve-shell, substantially asA and for the purposes described. v i

2. In a three-way valve for the purposes described, the cock H, having the chamber O, with the valve-seat c formed in its body, and two ports, d e, one entering` above and one below the valve-seat, in combination with the spring puppet-valve l?, substantially as and for the purposesv described.

3. In a three-wayvalve for the purposes described, the cock H, having the minor ports d e, sage through the valve, substantially as de-A scribed, in combination with the brake-handle L, friction-spring M, and index-ring N, the latter provided with the offset or shoulwhich form a differential pressure-pas- 1 IOO der j, which forms a stop for the brake-handle, thereby indicating the position in which communication through the valve .is established by the minor ports in the cock, substantially as described.

4. In an engineers brake-valve for automatic air-brakes, a three-way-cock valve having the ports C B D and I K, by means of which the iiow of air from the main reservoir into the brake-pipe and from the brake-pipe to the atmosphere is regulated, in combination with minor ports cl e, forming a differential air-pressure passage through the cock and ports g h in the valve-shell, adapted to register therewith and complete the differential air-pressure passage from the reservoir to the brake-pipe, substantially as described.

5. In an engineers brake-valve for automatic air-brakes, the combination of athree- Way-cock valve having the usual ports for connecting the main reservoir with the brake- IIO` pipe and the brake-pipe with the atmosphere, anda minor passage through its cock bymeans of which a differential air-pressure passage between the reservoir and the brakepipe is established, and the index-ring N, having stop t, forming the. shoulders j and k, by means of which the running position and the lap position of the lever are defined, substantially as described.

Witnesses: FREDERICK A. MCARTHUR.

H. S. SPRAGUE, CHARLEs J. HUNT. 

